@c ----------------------------------------------------------------------
@node fabs, math
@findex fabs
@subheading Syntax

@example
#include <math.h>

double fabs(double x);
@end example

@subheading Description

This function computes the absolute value of its argument @var{x}.

@subheading Return Value

@var{x} if @var{x} is positive, else -@var{x}.  Note that in this
context, +0.0 is positive and -0.0 is negative.  Infinities and
@code{NaN}s are returned unchanged, except for the sign.

@subheading Portability

@portability ansi, posix